Plastering composition and method of making same.



UNITED STAT S PATENT OFFICE.

GEORGE A. ESCH, OF SANDUSKY, OHIO.

P LASTERING COMPOSITION AND METHOD OF MAKING SAME.

SPECIFICATION forming part of Letters Patent No. 627,910, dated June 27,1899.

Application filed February 20,1899. Serial No. 706,164. (No specimens.)

To all whom it may concern.-

Be it known that I, GEORGE A. ESCH, acitizen of the United States,residing at Sandusky, in the county of Erie and State of Ohio, haveinvented certain new and useful Improvements in Plastering Compositionsand in the Methods of Making the Same, of which the following is a full,clear, and exact description.

My invention relates to a compound used in making what is known asa hardfinish for walls, ceilings, and the like, more particularly known as awhite-finish coat, al-' though it is obvious the compound may be usedwith various tinting or coloring agents.

The object of the invention more especially is to retard the setting ofthe coat and give opportunity to the plasterer to smooth and neatlyfinish the surface.

In carrying out my invention I take gypsum, in bulk, and unslaked lime,also in bulk,

' and put these substances in what is technically termed a cracker ormill, by the action of which they are reduced to small lumps, afterwhichoperation they are thrown together into a mill, preferably of thebur-stone type, and reduced to a powder of the nature of flour. Thepowder thus formed is next placed while dry in a kettle or receptacle,to which heat is applied, the temperature being raised above theboiling-point of water, whereupon the greater part of the moistureeliminated from the gypsum,which is considerable,is absorbed by thelime, the result being the slaking of the latter. This operation resultsin the calcination of the gypsum and the slaking of the lime. Theproportions of gypsum and unslaked'lime thus ground and treated togethermay be stated as six thousand two hundred pounds of gypsum to eighteenhundred and fifty pounds of lime, their mixture in these quantitieshaving been found to produce good results. I do not, however, limitmyself to exact proportions. The grinding and reduction to a powder ofthe gypsum and unslaked lime together effect an intimate combination ofthe two substances.

Heretofore where the lime has been slaked separately from the gypsumthere have been left unslaked small lumps of lime, resulting, when thecompound has been used in the plastering operation, in the production ofcracks and other defects in the surface. These defects, as has beendemonstrated, are avoided in the use of my compound, this desirableresult being due to the intimate combination effected between the gypsumand the lime and the perfect slaking of the latter by the moistureeliminated from the gypsum during the heating process. A portion of thismoisture, of which the gypsum contains a considerable quantity, willpass off into the atmosphere during the heating process, but the greaterportion will be absorbed by the lime effecting the slaking.

During the heating or boiling, hereinbefore described, glue and boraxpreviously dissolved in water may be poured into the kettle or heater,the proportions for the amount of gypsum and lime specified being aboutfifteen and six-tenths pounds of glue and eighteen andthree-fourthsounces of borax, only sulficient water having been used todissolve these ingredients. After the addition of. the dissolved glueand borax the boiling or heating of the entire compound or mixture iscontinnod for a short time, after which the receptacle or kettle isemptied of its contents,which on cooling become a hard-finish compoundin the form of powder.

In using this compound sufficient water is added to form it into a pasteor putty, in which condition it is ready to be applied to walls,ceilings, or the like in the same manner as the old-stylelime-and-plaster finish has been used, and when so applied it makes ahard smooth finish coat, commonly known as a hard finish. As abovestated, it is preferably used as a white-finish coat, but is capaa 1.The herein-described plastering compotenths pounds, and borax, eighteenand threefourths ounces, all treated and combined substantially asspecified.

3. The method herein described of making a plastering composition forhard finish, the

same consisting in reducing to powder to-' gether gypsum and unslakedlime, and applying heat to and boiling the mixture, the moistureinherent in the gypsum effecting the slaking of the lime during theheating process, substantially as set forth.

4;. The method herein described of making a plastering composition forhard finish, the same consisting in reducing to powder together gypsumand unslaked lime in substantially the proportions specified, andapplying heat to and boiling the mixture, the moisture in the gypsumeffecting the slaking set forth.

In testimony whereof I hereunto set my hand and seal.

GEORGE A. ESCII. [L. s.] I Witnesses THOMAS M. SLOANE, FRANK G. SLOANE.

